System for continuously measuring forces applied to the foot

Abstract

A self-contained system for measuring forces applied to the foot of a user includes a force sensor array positioned within the user's shoe between the foot and the inner sole of the shoe, the force sensor array including a multiplicity of individual force sensors arranged in a pattern that covers the entire area of contact between the sole of the user's foot and the inner sole of the shoe, an electronic circuit module removably attached to the side of the shoe, and a flat interconnecting cable for electrically coupling the force sensor array to the electronic circuit module. The electronic circuit module includes a central processing unit, read-only memory, random access memory, and scanning circuitry for electronically continuously scanning the force sensor array to obtain information indicative of an instantaneous force sensed by each one of the multiplicity of individual force sensors of the force sensor array, for processing that information to obtain force data, and for storing the force data in the random access memory. An annunciator audibly signals the user when a force on the foot greater than a predetermined threshold force is sensed.

We claim: 
     
       1. A self-contained system for measuring forces applied to the foot of a user, the system comprising: a force sensor array positioned within a shoe worn by the user such that said force sensor array lies between the user's foot and an inner sole of the shoe, said force sensor array comprising a multiplicity of individual force sensors arranged in a pattern that covers the entire area of contact between the sole of the user's foot and the inner sole of the shoe;   an electronic circuit module adapted for attachment to said shoe; and   interconnection means for electrically coupling the force sensor array to the electronic circuit module;   said electronic circuit module being operative for electronically continuously scanning said force sensor array to obtain information indicative of an instantaneous force sensed by each one of said multiplicity of individual force sensors comprising said force sensor array;   said electronic circuit module comprising:   scanning circuitry for scanning said force sensor array;   central processing means for executing instructions controlling said scanning circuitry and for processing said information indicative of the instantaneous force sensed by each one of said multiplicity of individual force sensors comprising said force sensor array to obtain force data;   clock means coupled to said central processing means for providing date and time of day information thereto;   read-only memory means coupled to said central processing means for storing routines and subroutines of instructions to be executed by said central processing means during a system boot period of operation; and   random access memory means for storing additional routines and subroutines of instructions to be executed by said central processing means subsequent to said system boot period of operation and for storing said force data.   
     
     
       2. A self-contained system for measuring forces applied to the foot of a user as in claim 1 wherein said electronic circuit module is adapted for removable attachment to a side of said shoe. 
     
     
       3. A self-contained system for measuring forces applied to the foot of a user as in claim 1, further comprising: annunciator means for providing an audible signal to the user of certain system operating conditions;   said central processing means is operative for accumulating said instantaneous force sensed by each one of said multiplicity of individual force sensors and for comparing the accumulated force to a predetermined threshold force and for causing said annunciator means to audibly indicate an accumulated force that exceeds said predetermined threshold force.   
     
     
       4. A self-contained system for measuring forces applied to the foot of a user as in claim 1, further comprising wireless data transmitter means for coupling said central processing means to a remotely located computer to enable the transfer of selected information, including said force data, between said central processing means and said external computer. 
     
     
       5. A self-contained system for measuring forces applied to the foot of a user, the system comprising: a force sensor array positioned within a shoe worn by the user such that said force sensor array lies between the user's foot and an inner sole of the shoe, said force sensor array comprising a multiplicity of individual force sensors arranged in a pattern that covers the entire area of contact between the sole of the user's foot and the inner sole of the shoe;   an electronic circuit module adapted for attachment to said shoe; and   interconnection means for electrically coupling the force sensor array to the electronic circuit module;   said electronic circuit module being operative for electronically continuously scanning said force sensor array to obtain information indicative of an instantaneous force sensed by each one of said multiplicity of individual force sensors comprising said force sensor array;   said force sensor array comprising:   top and bottom electrode layers, said top and bottom electrode layers including corresponding pluralities of vertically coincident and horizontally equidistantly spaced individual sensor electrodes, the pluralities of individual sensor electrodes of each of said top and bottom electrode layers being arranged to form substantially parallel equidistant lines of sensor electrodes positioned diagonally with respect to a longitudinal axis of said shoe, the individual sensor electrodes of a given diagonal line of sensor electrodes being electrically serially connected by a conductive trace that follows a nonlinear path;   at least one partially conductive pressure sensitive coating sandwiched between said top and bottom electrode layers;   top and bottom substrate layers overlying said top and bottom electrode layers, respectively, each of said top and bottom substrate layers comprising a lattice structure having a plurality of cutouts in areas not directly overlying said pluralities of individual sensor electrodes; and   top and bottom conductive trace layers overlying said top and bottom electrode layers, respectively, each of said top and bottom conductive trace layers including a plurality of conductive traces, each of said conductive traces being electrically connected through a corresponding one of said top and bottom substrate layers to a particular one of the said diagonal lines of sensor electrodes of a corresponding one of said top and bottom electrode layers.   
     
     
       6. A force sensor array adapted for positioning within a shoe to sense the forces applied thereto by the user's foot, the force sensor array comprising: top and bottom electrode layers, said top and bottom electrode layers including corresponding pluralities of vertically coincident and horizontally equidistantly spaced individual sensor electrodes, the pluralities of individual sensor electrodes of each of said top and bottom electrode layers being arranged to form substantially parallel equidistant lines of sensor electrodes positioned diagonally with respect to a longitudinal axis of said shoe, the individual sensor electrodes of a given diagonal line of sensor electrodes being electrically serially connected by a conductive trace that follows a nonlinear path;   at least one partially conductive pressure sensitive coating sandwiched between said top and bottom electrode layers;   top and bottom substrate layers overlying said top and bottom electrode layers, respectively, each of said top and bottom substrate layers comprising a lattice structure having a plurality of cutouts in areas not directly overlying said pluralities of individual sensor electrodes, each of said top and bottom substrate layers comprising a flexible dielectric film; and   top and bottom conductive trace layers overlying said top and bottom electrode layers, respectively, each of said top and bottom conductive trace layers including a plurality of conductive traces, each of said conductive traces being electrically connected through a corresponding one of said top and bottom substrate layers to a particular one of the said diagonal lines of sensor electrodes of a corresponding one of said top and bottom electrode layers.   
     
     
       7. A force sensor array adapted for positioning within a shoe to sense the forces applied thereto by the user's foot, the force sensor array comprising: top and bottom electrode layers, said top and bottom electrode layers including corresponding pluralities of vertically coincident and horizontally equidistantly spaced individual sensor electrodes, the pluralities of individual sensor electrodes of each of said top and bottom electrode layers being arranged to form substantially parallel equidistant lines of sensor electrodes positioned diagonally with respect to a longitudinal axis of said shoe, the individual sensor electrodes of a given diagonal line of sensor electrodes being electrically serially connected by a conductive trace that follows a nonlinear path;   at least one partially conductive pressure sensitive coating sandwiched between said top and bottom electrode layers;   top and bottom substrate layers overlying said top and bottom electrode layers, respectively, each of said top and bottom substrate layers comprising a lattice structure having a plurality of cutouts in areas not directly overlying said pluralities of individual sensor electrodes, each one of said plurality of cutouts in each of said top and bottom substrate layers being hexagonal in shape; and   top and bottom conductive trace layers overlying said top and bottom electrode layers, respectively, each of said top and bottom conductive trace layers including a plurality of conductive traces, each of said conductive traces being electrically connected through a corresponding one of said top and bottom substrate layers to a particular one of the said diagonal lines of sensor electrodes of a corresponding one of said top and bottom electrode layers.   
     
     
       8. A force sensor array adapted for positioning within a shoe to sense the forces applied thereto by the user's foot, the force sensor array comprising: top and bottom electrode layers, said top and bottom electrode layers including corresponding pluralities of vertically coincident and horizontally equidistantly spaced individual sensor electrodes, the pluralities of individual sensor electrodes of each of said top and bottom electrode layers being arranged to form substantially parallel equidistant lines of sensor electrodes positioned diagonally with respect to a longitudinal axis of said shoe, the individual sensor electrodes of a given diagonal line of sensor electrodes being electrically serially connected by a conductive trace that follows a nonlinear path;   at least one partially conductive pressure sensitive coating sandwiched between said top and bottom electrode layers;   top and bottom substrate layers overlying said top and bottom electrode layers, respectively, each of said top and bottom substrate layers comprising a lattice structure having a plurality of cutouts in areas not directly overlying said pluralities of individual sensor electrodes, each of said top and bottom substrate layers comprising a partially conductive pressure sensitive coating; and   top and bottom conductive trace layers overlying said top and bottom electrode layers, respectively, each of said top and bottom conductive trace layers including a plurality of conductive traces, each of said conductive traces being electrically connected through a corresponding one of said top and bottom substrate layers to a particular one of the said diagonal lines of sensor electrodes of a corresponding one of said top and bottom electrode layers.